ESP32 IP address fail

sivar2311 · September 22, 2025, 3:19pm

Do this step by step.

Forget about static IP.
Make your network work correctly (with DHCP).
If everything works correctly (and you still need static IP) go for the static IP.

trevor1 · September 22, 2025, 3:26pm

Doing some research now

trevor1 · September 25, 2025, 1:34pm

Hi Boris, quick update ….

My ESP32 project going fine now, making a lot of progress.

My Wifi system not great, I’ve turned off the remote Mercusys Halo S3 unit for now.

Works fine for internet, whatsApp, etc on phone / laptop in workshop, but I just can’t stop it creating its own subnet. Might need better equipment. I’ll keep researching.

Anyway, thank you so much for all your help !

maxgerhardt · September 25, 2025, 3:41pm

Just FYI, even without a static IP you can use the mDNS technology and make the ESP32 advertise under a hostname, like esp32.local, which should then be recognized by all modern operating systems and browsers, so that you can just go to http://esp32.local to access the board.

github.com/espressif/arduino-esp32

libraries/ESPmDNS/examples/mDNS_Web_Server/mDNS_Web_Server.ino

372ba6a40


      
          // Set up mDNS responder:
          // - first argument is the domain name, in this example
          //   the fully-qualified domain name is "esp32.local"
          // - second argument is the IP address to advertise
          //   we send our IP address on the WiFi network
          if (!MDNS.begin("esp32")) {
            Serial.println("Error setting up MDNS responder!");
            while (1) {
              delay(1000);
            }
          }

trevor1 · September 26, 2025, 4:31pm

Thanks for the info Max, I’ll do some experiments over the weekend and get back to you.

Trevor

hafilatbalance · September 4, 2026, 3:46pm

If WhatsApp still works, which suggests the ESP32 is actually reaching the internet. First check the IP printed by the ESP32 against your router’s DHCP/client list and print the subnet mask and gateway too. If it still reports “connected” with the router completely powered off, you may be connecting to a different Wi-Fi network or seeing a stale/static IP in the code. Check that you’re using WiFi.localIP() and not a manually assigned address, and remove any WiFi.config() call while testing.